Category: MK Electric Socket Outlet Positioning Guide
Email MK Electric
MK Electric
Provision of Socket Outlets
Recently, in the UK Electrical Trade Press, there has been criticism
of the ring circuit and BS 1363 plugs and sockets.
The British ring circuit was introduced to specifically address a number
issues:
- Provide a multitude of sockets
- Minimise the number of final circuits
- Maximise diversity of loading
- Provide greater safety against fire & shock
- Provide correct overload protection of flexible cables &
appliances
- Remove need to use trailing sockets
The ring circuit provides the most flexible system, allowing
additions by breaking into the ring or adding a connection unit. This
can be done, whilst ensuring the overload protection to the additional
loads will be maintained through the use of fused plugs or fused
connection units.
The alternative, radial circuits run the risk of damage from overloads
and over currents as the rating of the protective device exceeds that of
the flexible cable and appliance.
The table below shows the number of devices and size of cable that can
be used for each circuit.
At the present time there are no requirements in place for the provision
of socket outlets in the home as far as BS 7671:2001 – IEE Wiring
Regulations, 16th Edition are concerned†.
Regulation 553-01-17 states that where portable equipment is likely
to be used, provision shall be made so that the equipment can be fed
from an adjacent and conveniently accessible socket-outlet, taking
account of the length of flexible cord normally fitted to portable
appliances and luminaries.
It does not give any specific requirements for the number of sockets,
neither can any be found in the Building Regulations for England and
Wales, however the Scottish Building Regulations mention certain
requirements, these can be found in Section 4 of the “Domestic General”
regulations. These state in:
4.6.4 to reduce both overloading and trip hazards a minimum number of
socket outlets should be provided:
- 6 x 13A sockets within the kitchen
- 4 x 13A sockets within each apartment*
- 4 additional 13A socket outlets anywhere else in the dwelling
*apartment means a room within a dwelling not used solely as a
kitchen, store or utility room
Generally throughout the UK there are not enough socket outlets to
provide power to electrical equipment in the home – the increase in
ownership of electrical consumer durables can lead to the increased use
of extension cables and adaptors which can lead to both trip hazards and
overloading problems.
One way to remove this problem, especially where the usage of
multimedia items is concerned, is to use combination plates, which have
a number of 13 amp socket outlets and the facility to connect audio
visual and telecoms outlets.
The National House-Building Council (NHBC) sets out the standards for
new and refurbishment buildings, however their advice is seldom
followed. The Copper Development Association are pushing for a change to
set minimum requirements for the number of sockets, a recent survey
conducted by the ECA found that over 50% of installations in new housing
are believed to have socket additions in the first 12 months.
The following table has been produced by the IEE in conjunction with ECA,
Select, NHBC, CDA and EIEMA and published in their On Site Guide and
shows the recommended provision of socket outlets.
*It should be noted that the number of sockets is dependent on the
size of the room.
Source: Table 8B, appendix B, On Site Guide BS 7671:2001 (2004)
The Wiring regulations† have the following key points to make when it
comes to plugs and sockets.
553-01-01 Every plug and socket outlet shall comply with all the
requirements of items (i) and (ii).
Except for SELV circuits, it shall not be possible for any pin of a plug
to make contact with any live contact of its associated socket-outlet
while any other pin of the plug is completely exposed, and It shall not
be possible for any pin of a plug to make contact with any live contact
of any socket-outlet within the same installation other than the type of
socket-outlet for which the plug is designed.
This means that plugs should not be transferable between different
outlets as is the case with some continental outlets, and shall have
sleeved pins.
553-01-03 Except where Regulation 553-01-05 applies, in a low voltage
circuit every plug and socket outlet shall confirm with the applicable
British Standard listed in Table 55A (plugs and socket-outlets for low
voltage circuits.
553-01-04 Every socket-outlet for household and similar use shall be
of the shuttered type and, for an a.c. installation, shall preferably be
of a type complying with BS 1363.
†Some references may change in the proposed update to the IEE Wiring
Regulations - 17th Edition, due forpublication on January 1st 2008
Information associated with: MK Electric - Electrical Accessories incl
wiring devices, lighting switches & consumer units
|
Email this company
MK Electric
The Arnold Centre
Paycoke Road
Basildon
Essex
SS14 3EA
Tel: +44 (0) 1268 563000
Fax: +44 (0) 1268 563405
Literature Helpline:
+44 (0) 870 240 3385
|
Request
Information other products